Listeria (cont.)

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What are listeriosis symptoms and signs?

  • Fever, muscle aches, and occasionally, nausea or diarrhea (or both) are the usual symptoms associated with listeriosis.
  • Some individuals may also experience fatigue and a decrease or loss of appetite.
  • These symptoms usually last up to one week and spontaneously resolve.

However, in some people, the organisms can spread to the brain.

  • The symptoms of meningitis (stiff neck, headache, and fever),
  • altered mental status (confusion, reduced mental activity),
  • loss of balance problems, and seizures (convulsions) may develop in brain infections.
  • Brain abscesses may also occur and cause similar symptoms.
  • The incubation period between exposure and symptoms is quite variable (three to 70 days, with 21 days as average) and may extend up to about two months or more according to some investigators.

Pregnant women who are otherwise healthy usually have only minor symptoms. However, Listeria organisms in pregnant females often cause: 

  • miscarriage,
  • stillbirth,
  • premature birth, or
  • cause infection and,
  • potentially, death of newborns.

Breastfeeding in humans has not been shown to transmit the bacteria to newborns; however, animal studies show the organisms are transferred in breast milk of other mammalian species. Researchers consider it is theoretically possible for the organisms to be transmitted in human breast milk.

Occasionally, localized skin infections may occur, especially in people who handle animals that are infected with Listeria. These skin infections rarely lead to further complications such as brain infection.

Medically Reviewed by a Doctor on 4/10/2015

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Listeriosis - Causes Question: Please discuss your experience with listeriosis, including a possible cause.
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